Glial distribution of Cu/Zn SOD immunoreactivity in intact immature brain. Cu/Zn SOD was not observed in the GFAP-expressing astrocyte population of the brain parenchyma (A: cortex, confocal image). However, GFAP-expressing astrocytes showed co-localization with Cu/Zn SOD in the glia limitans (C, confocal image) and in the ventricle walls (B: third ventricle; arrow: tanycyte). Microglial cells and endothelium (arrow), identified with tomato lectin histochemistry, were negative for Cu/Zn SOD (D: cortex; confocal image). Scale bars in A: 40 μm; in B, C and D: 20 μm.